The invention relates to topical pain relief compositions for applying to the skin of a patient, and to cream-type carrier compositions or bases for use with topical pain relief medicaments.
It has been proposed to use compounds for topical pain relief which have not had widespread use as such, such as ketamine and amitriptyline. These compounds may provide pain relief in some circumstances when applied topically. However, it has been found that their use as topical pain relief medicaments is highly dependent on the selection of a suitable carrier. Previous proposals have related to mixing such medicaments with a cream-type base, for applying on the skin of a patient. However, suitable topical pain relief properties of these compounds require admixture with a carrier which achieves a suitable delivery to the skin of a patient. Improved delivery of such medicaments may be achieved with a suitable carrier having enhanced properties for delivering the medicinal compounds to the skin of a patient in a manner which enhances absorption by the patient""s skin over a suitable period of time.
The invention further relates to an improved method for preparing a cream-based carrier for use with a topical pain relief medication such as ketamine or amitriptyline.
The present invention relates to an improved composition for topically delivering medicaments, including medicaments having analgesic properties, such as ketamine, which results in a more profound pharmacological effect than cream-type carriers previously proposed.
The use of amitriptyline hydrochloride, e.g., N-(2-amino cycloaliphatic) benzamides and napthamides, for pain relief is known. See e.g. U.S. Pat. No. 4,148,914 by Szmuszkovicz. Likewise, ketamine hydrochloride is known to have a variety of medical uses. Use of such compounds for topical application for pain relief has been limited by an inability to provide a suitable and effective carrier.